Permanent-type well packer



Nov. 6, 1962 c. c. BROWN PERMANENTTYPE WELL PACKER 3 Sheets-Sheet 2 Filed May 11, 1959 C/CERO C. BROWN IN V EN TOR.

A TTORN E Y Nov. 6, 1962 c. c. BROWN 3,062,291

- PERMANENT-TYPE WELL PACKER Filed May 11, 1959 3 Sheets-Sheet 5 j/AY/A IN V EN TOR.

T 52 .9 5%.10 BY e ATTORNEY- l P C/CERO 6. BROWN United States Patent Ofilice 3,062,291 Patented Nov. 6, 1962 3,062,291 PERMANENT-TYPE WELL PAKER Cicero C. Brown, Houston, Tex., assignor to Brown Gil Tools, Inc., Houston, Tex., a corporation of Texas Filed May 11, 1959, Ser. No. 812,263 9 Claims. (Si. 166-119) This invention relates to well packers and particularly to well packers of the so-called permanent-type packers. These packers are designed, when once set in the well, to remain permanently, but are ordinarily constructed of materials such that they may be readily destroyed by drilling tools when necessary or desirable to remove them.

More conventional types of packers of the general character described are designed to be run either on Wire line setting strings or on tubing strings. in both cases, however, these conventional packers require that the setting strings and setting tools, whether a wire line or tubing string is employed, must be removed from the well before the string of production tubing is run into the well and connected to the packer. These more conventional types of packers, therefore, require a multiplicity of operations before the well is equipped for production, and in these operations, control of the well is not feasible or as complete as is desirable, particularly when high pressures are present in the formations penetrated by the well bore.

The present invention has for its principal object the provision of a permanent-type drillable packer which overcomes the major disadvantages of existing designs, such as are noted above, in that it may be run on the production tubing string itself, and before any circulation operations or manipulation operations to set the packer, may be placed in final position in the Christmas tree and thereby permit the blowout preventers to be removed. This permits maintaining the well under complete control throughout the subsequent operations of preparing the well for production and setting the packer; that is, the mud materials may be circulated out of the well and the face of the sand or other producing formation washed to the point at which it is ready to flow before the packer is even set. No setting tools are required to be removed and the entire setting operation is greatly simplified and conducted under secure well control conditions.

An important object of the present invention is to provide a form of packer of the type described in which the packer is set hydraulically, thereby minimizing the mechanical manipulations which are frequently troublesome in setting packers.

Another important object resides in the employment of a packer structure having oppositely acting anchor and seal assemblies operable to anchor the structure in the Well casing against movement in either direction while sealing with the well casing, and employing a hydraulically-actuated piSton and cylinder arrangement for setting the anchor and seal elements of the assemblies.

Still another obiect is the provision of a hydraulicallyactuated packer structure of the type described, having a valve member for closure the bore of the packer structure upon withdrawal of the operating stem in order to prevent back-flow of pressure fluid from below the packer when the operating stem is out of the packer.

A more specific object is the provision of two longitudinally spaced releasable latch mechanisms for releasably securing the operating stern in the packer body and which will prevent premature setting of the packer.

Other and more specific objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawing which illustrates a useful embodiment in accordance with this invention.

In the drawing:

FIGS. 1 and 2 are longitudinal, partly sectional, views, showing the packer structure positioned in a well casing and illustrating two stages in the operation of the packer;

FIG. 3 is a view generally similar to FIG. 2, but showing the operating stem Withdrawn and the back pressure valve in the closed position;

FIG. 4 is a cross-sectional view along line 4-4 of FIG. 1;

FIGS. 5 and 6 are enlarged fragmentary views illustrating some of the details of the packer structure;

FIGS. 7 and 8 are schematic views illustrating the packer employed with a single string of tubing, FIG. 8 showing the tubing string being withdrawn from the packer; and

FIGS. 9 and 10 are schematic views, generally similar to FIGS. 7 and 8, illustrating the present invention employed in conjunction with an additional packer in multiple well completions.

Referring to the drawing, and more particularly to FIGS. 1 and 2, the packer structure S comprises a generally tubular body 10 having its upper end threadedly received in the bore of an upper collar 11 provided with a lip 12 which extends inwardly over the upper end of body 10 and forms a short flush extension thereof. The upper end of lip 12 is chambered to provide a seat 13, for purposes to be described subsequently. The lower end of body 10 is threadedly received in a lower collar 11b. Collars 11 and 11b define external longitudinally spaced opposed shoulders 11a and 110, respectively, about the exterior of body 10 against which are seated a pair of longitudinally spaced upper and lower anchor-and-seal assemblies of identical form, each designated generally by the numeral 15.

Each of the assemblies 15 comprises the following successively arranged elements: an annular resilient seal element 17 constructed of rubber or other flexible resilient composition material abutting shoulders 11a and file; an expander 18 having one end abutting seal element 17 and having a conical surface 19 tapering inwardly toward body 10; a set of wedge-shape pipe-gripping slips 20 which are secured to the expander in longitudinally retracted position by means of a shear screw 21 which extends through registering openings in the adjacent tip portions of slips 20 and expander 18. The inner faces of slips 20 have outwardly tapering surfaces complementing the taper of surface 19. The inner end of shear screw 21 is reduced in diameter to form the end portion 22 which extends into a recess 23 provided in the exterior of body 10 (FIG. 6).

End portions 22 of the shear screws 21 will be dimensioned to have substantially lesser breaking strength than the bodies of shear screws 21. As an example of the relative strengths which will function satisfactorily for the purposes of this invention, portions 22 may be made to have a breaking strength such that it will shear when the pressure in the hydraulic cylinder, to be described later, attains about 1000 lbs. per square inch, while the larger portions of the shear screws will be made to break when said pressure attains about 3000 lbs. per square inch. These values may, of course, be varied depending on the service conditions obtaining in each instance. By this arrangement, it will be seen that shear screw 21 secures the slips 20 to expander 18 against relative movement therebetween and also simultaneously secures both of these elements to body 10, also against movement relative thereto, the slip expander being thereby initially held in retracted or non-setting position. It will be seen that the upper and lower anchor-and-seal assemblies, expanders 13 tapering inwardly toward each other, are arranged to act in opposite directions so that actuation of the assemblies will anchor the packer structure against movement in either direction when the structure has been set in a well casing, as will be subsequently described.

Positioned concentrically about the exterior of body 10, between the upper and lower anchor-and-seal assemblies 15, is an actuating assembly, designated generally by the numeral 25, which comprises a tubular cylinder 27 concentrically surrounding a piston 26 and secured at its upper end to an annular head 28 forming a closure for the upper end of the cylinder. Cylinder 27 is longitudinally slidable relative to piston 26. The latter is provided, at its lower end, with an annularly enlarged head 29 defining an upwardly facing annular shoulder 30 forming a limit stop for the lower end of cylinder 27. The lower end of head 29 abuts against the base of lower slips 2%), while the upper end of head 28 similarly abuts against the base of upper slips 20. Piston 26 is provided with an internal seal 31 to form a fluid-tight seal between the piston and the exterior of body 10 and is provided, near its upper end, with an external seal 32 to seal between the exterior of the piston and cylinder 27. Head 28 of the cylinder is similarly provided with an internal seal 33 for sealing between body 10- and head 28 and an external seal 34 for sealing between the head 28 and cylinder 27. In the fully telescoped position, illustrated in FIG. 1, a space is provided between piston 26 and head 28 defining a piston chamber 35. One or more radial ports 36 are provided through the wall of body 10 communicating with chamber for admission thereto of pressure fluid, as will be subsequently described.

Body 10 has an axial bore 37 into which extends a tubular operating stem or mandrel, designated generally by the numeral 38. Mandrel 38 comprises co-axially connected upper, intermediate, and lower sections 38a, 38b and 38c, respectively. The external diameters of upper sections 38a is somewhat smaller than that of intermediate section 38b and is threaded at its lower end for threaded reception in an internally threaded socket 39 formed in the upper end of intermediate section 38b. The larger external diameter of the latter defines an annular upwardly facing shoulder 40 about the lower end of the upper section 38a. The lower end of intermediate section 38b is reduced in diameter to define the downwardly facing shoulder 41 about the lower end of intermediate section 3811 and the reduced lower end portion of the latter is externally threaded to form the pin connection 42 for reception in a coupling collar 43, the lower end of which threadedly receives the upper end of lower mandrel section 38c to complete the connections between the mandrel sections. The upper end of collar 43 forms an upwardly facing shoulder 44 spaced from shoulder 41 and a packing 45 is mounted about pin connection 42 in the space between these shoulders for compression therebetween when the pin connection is screwed into collar 43 whereby to cause packing 45 to form a fiuid-tight slidable seal between mandrel 38 and body 10.

At its upper end, upper mandrel section 33a is externally enlarged forming the head 46 and defining the downwardly facing external shoulder 47. Head 46 is provided with the internally threaded socket 48 by which the mandrel 38 may be secured to the lower end of a tubing string 50. The latter (FIG. 7) extends upwardly through a Well casing C and a wellhead H at the surface. A valve V controls flow through the tubing string.

The exterior of intermediate mandrel section 38b is reduced somewhat in diameter over a portion of its length to form the annular chamber 51 between intermediate section 38b and the interior wall of body 10. The reduction in diameter of section 38b defines at its lower end the downwardly and outwardly tapering annular shoulder 52. One or more radial ports 53 are provided through the wall of section 38b above shoulder 52 to provide fluid communication between the bore of mandrel 38 and chamher 51. It will be seen from the arrangement of these parts that when mandrel 38 is in the fully telescoped position, illustrated in FIG. 1, chamber 51 will be in communication with ports 36 and thence with piston chamber 35, while the seal formed by packing 45 will be positioned below ports 36 and 53.

Upper collar 11 is counter-bored above the lip 12 to form the internally threaded socket 55 into which is screwed a short tubular extension 56 having at its upper end the inwardly bevelled seat 57 adapted to be engaged by shoulder 47 when mandrel 38 is fully telescoped into body 10. Extension 56 forms part of an upper latch mechanism by which the upper end portion of mandrel 38 may be releasably secured to the packer body and which permits the mandrel to be withdrawn from the body, after the packer is set, by application of a straight upward pull to the mandrel. This latch mechanism is disclosed and described in greater detail in my co-pending application Serial No. 756,522, filed August 28, 1958 for a Coupling Device.

This latch mechanism comprises a ring 60 which is supported on upper mandrel section 380 on a narrow ledge 61 spaced a slight distance below shoulder 47. Ring 60 has formed integrally therewith a plurality of angularly spaced depending fingers 62 of resilient construction and having pawls or dogs 63 on their lower ends which project radially into a counter-bore 64 in the lower end of extension 56, the upper end of the counter-bore terminates at the downwardly bevelled shoulder 13. Dogs 63 have their upper and lower ends tapered to complement shoulders 65 and 70, respectively.

A keeper sleeve 66 is slidably mounted on mandrel section 38a between the latter and the upper end of body 10, the keeper sleeve being positioned above shoulder 40. A packing 67 is mounted about mandrel section 38a below keeper sleeve 66, and a thrust ring 68 is positioned below packing 67 and urged thereagainst by a coil spring 69 disposed between shoulder 40 and ring 68. Spring 69 not only compresses packing 67, thereby forming a slidable seal between mandrel section 38a and body 10, but also urges keeper sleeve 66 upwardly. The upper end of keeper sleeve 66 has a downwardly and outwardly and bevelled end face 70 adapted to engage a similarly sloping end face on dogs 63, thereby being operable to urge the dogs outwardly into counterbore 64, and to cause the dogs to engage shoulder 65 when the keeper sleeve moves upwardly to the position shown in FIG. 2, in a manner to be subsequently described. A narrow shoulder 71 limits the upward movement of keeper sleeve 66 on mandrel section 38a to prevent keeper sleeve 66 from attaining a point above dogs 63. The operation of the latch mechanism will be described more fully hereinafter.

Body 10 is provided with a plurality of circumferentially spaced radial openings 73 which are constricted slightly at their outer ends at 74 to define sockets for the reception of ball-shaped latches 75 which project outwardly through the constricted end 74 into engagement with shoulder 52 when the mandrel member is fully telescoped in body 10, as illustrated in FIGS. 1 and 5. In its fully retracted position, piston member 26 will extend upwardly past ball latches 75, the clearance between piston 26 and body 10 being such that the outer surface of the piston will hold the balls in engagement with shoulder 52, thereby providing a latching arrangement by which mandrel 38 cannot be drawn upwardly relative to body 10 while the ball latches are engaged with shoulder 52. When piston member 26 has moved downwardly in response to hydraulic pressure, as best seen in FIGS. 2 and 3, ball latches 75 will be released for movement outwardly of openings 73 into chamber 35 and when so released, it will be seen that the mandrel may be drawn upwardly relative to body 10.

Lower collar 11b has a longitudinally slotted tubular extension 76 which is commonly termed a junk pusher or scraper, by which mud or other detritus, present on the wall of the well casing in which the packer is ru will be scraped or pushed out of the way and the surfaces thereby cleaned in advance of the packer structure. xtension 76 has mounted therein a flapper valve 77 which is pivotally secured at one side to the wall of extension 7o by means of a pivot pin 78. A spring 79 is coiled about pivot pin 78 and its ends engaged with valve 77 and collar 11b so as to resiliently bias valve 77 toward the closed position across bore 37. The lower end of mandrel section 38c is threadedly received in a collar having the threaded socket 80. The latter is provided with an internal shoulder 81 adapted to form a seat for a plugging element 82, as will be subsequently described.

The above described device is operated in the following manner: Operating mandrel 38 will be secured to tubing 50 and inserted into body 10 with shoulder 47 engaging shoulder 57, the fully telescoped position of the mandrel. The lower end portion of mandrel section 38c will project below body 10 and will hold flapper valve 77 in its open position (FIGS. 1 and 2). The other elements of the structure will be in the relative positions illustrated in FIG. 1 wherein it will be seen that ports 53 and 36 are in communication with the bore 37 of the mandrel and through this bore with the bore of tubing 50. Ball latches 75 will be engaged with shoulder 52. Thus, body 10 will be secured against upward move ment relative to mandrel 38 by the engagement of end face 57 with shoulder 47, and against downward movement relative to mandrel 38 by the engagement of ball latches 75 with shoulder 52. In the fully inserted position of mandrel 38, it will be seen that the annular space between the mandrel and body 10 will be sealed at longitudinally spaced points by means of packings 45 and 67, these seals being located, respectively, at points below and above the levels occupied by ports 53 and 36. With the structure thus mounted on the tubing string, the latter will be employed to lower the structure into a casing C (FIGS. 1 and 2) lining the well bore, and positioned therein, ordinarily at a point above perforations P (PIGS. 7 and 8) which communicate with a producing formation A. When the packer structure is in the proper position, the tubing will be set in wellhead H (FIG. 7) in the usual manner, and secured therein so that blowout preventers or other temporary elements of the Christmas tree may be removed and the tubing connections hooked up for a permanent ope-ration. Circulation may then be conducted through the tubing in order to wash the face of the formation and to remove heavy mud and the like from the interior of the casing, all in accordance with conventional practice. Since the packer has not yet been set, clearance is provided between the packer structure and the casing for the circulation of washing fluids.

When all such preliminary operations have been completed, a plug of any suitable and generally conventional form, such as a ball, designated generally by the numeral 82 (FIG. 1), will be dropped through the bore of the tubing and caused to move downwardly therein where it will be lodged on shoulder 81 in order to close off the bore of the operating mandrel. When plug 82 is in place, pumping of pressure fluid into the bore of the tubing and the operating mandrel will be conducted to build up fluid pressure interiorly of the mandrel. This fluid pressure will pass through openings 53 and 36 into chamber 35 to exert pressure between the opposed ends of piston 26 and cylinder head 28. This pressure will urge these elements apart and against the adjacent ends of slips and when the force thus exerted in the opposite direction upon slips 20 exceeds the breaking strength of the smaller end sections 22 of the shear screws, these end sections will be sheared along the plane of the exterior surface of body 10 (FIG. 2), and the continued movement of piston 26 and cylinder head 28 will then urge slips 2t) and expanders 18, which still remain connected by the shear screws, in opposite directions producing axial compression of sealing elements 17 and consequent radial expansion of the sealing elements into sealing engagement with the wall of casing C (FIG. 2). As the pressure in chamber 35 continues to be built up, producing further opposite movements of piston 26 and cylinder head 28, the increased pressure thus exerted in opposite directions will shear the larger diameter portions of shear screws 21 along the plane of surfaces 19 causing movement of the slips 20 relative to expanders 18, since further axial movement of the latter will be resisted by the previously expanded sealing elements which will be compressed against casing C. This relative movement will carry slips 20 into wedging engagement between expanders 18 and the wall of casing C and will thereby anchor the slips to the casing.

When the slips and seals have thus been set, by virtue of the fluid pressure exerted between piston 26 and cylinder head 28, the pressure may be relieved from the interior of the operating stem, and the natural resilience of sealing elements 17 will tend to urge expanders 18 toward and into expansive engagement with slips 20, thereby preventing release of the slips and effectively assuring permanent anchorage of the packer in the casing.

When the fluid pressure is applied piston member 26 is forced downwardly to a point below the positions of ball latches 75 releasing the latter for rearward or outward movement in openings 73, thereby releasing their engagement with mandrel 38. The fluid pressure applied to set the packer will also tend to urge the mandrel upwardly. However, the upper latch mechanism will prevent the mandrel from being forced out of the packer, as the fluid pressure, together with the pressure exerted by spring 69 through packing 67 on the lower end of keeper sleeve 66, will cause the latter to force dogs 63 against shoulder 65 (FIG. 2), thereby locking the mandrel to the body. The greater the fluid pressure, the stronger the holding force which will be exerted on the latching dogs.

With the packer thus set in the well, the fluid pressure in the bore of the tubing which was employed to set the packer will be relieved by opening suitable valves at the well. Thereupon fluids, such as oil or gas or both, will flow from formation A through perforations P and thence into the lower end of the mandrel where the well fluids will carry plug member 82 upwardly through the bore of the tubing string to the surface where it will be gemoved, opening the well to production from formation If, for any reason, it is desired to remove the tubing string, as for example to conduct operations in the well at a point above the packer, this can be readily accomplished with the above-described packer construction by merely applying an upward pull to the tubing string (FIG. 8). The reaction of this force through keeper sleeve 66 will compress spring 69 sufficiently to permit keeper sleeve 66 to retract enough to allow dogs 63 to slip upwardly over shoulder 65 and mandrel 38 may then be pulled upwardly of body 10, since ball latches 75 will previously have been released, as described. The described structure which permits the removal of the tubing string and mandrel by a straight upward pull, simplifies the removal operation and greatly reduces the hazards which arise in more conventional constructions which require rotation of the tubing string and some of the various latching elements to effect release from the packer. As the lower end of mandrel 38 is raised above flapper valve 77, the latter will swing across the bore of body 10 and close oil the latter against any pressures from below the packer which might be in excess of any pressures in the casing above the packer (FIGS. 3, 7 and 8). 3

When it is desired to run the tubing string back in the well, this can be accomplished by running the string and mandrel 38 back into the packer and as soon as packings 45 and 67 are inside bore 37, fluid pressure may be applied through the bore of the string to force flapper valve 77 back to the open position, aided by the weight of the tubing string when the end of mandrel section 38c is brought into contact with valve 77. The stting is then moved downwardly until latch dogs 63 are again positioned below shoulder 65.

As noted previously, once the packer has been set in the manner described, it is permanently set and can be removed only by drilling it out, or otherwise destroying it. For this reason all of the elements of the packer structure will be constructed of easily drillable or frangible materials suitable to render the packer structure easily destructible.

FIGS. 9 and 10 illustrate another application of a packer in accordance with the present invention to multiple completion systems, wherein two or more producing formations are produced from the same well bore through separate tubing strings.

In this embodiment, the packer S, of the kind previously described, is carried on the lower end of tubing string 59a and is adapted to be set, in the manner previously described, between formation A and a higher producing formation A Thus. production from formation A will be carried through tubing string 59a to the surface. Tubing string 59a will also have mounted on it at a point above formation A a second packer S of the eneral type disclosed in co-pending application Serial No. 677,592, filed August 12, 1957 by the present applicant and Chudleigh B. Cochran, now US. Patent No. 2,950,761. Packer S is provided with a tubular seat D (FIG. 10), into which a second string of tubing 50]) may be inserted from the surface, and the weight of string 5011 applied to packer S to anchor the latter and expand the seals E (FIG. 9), thereby effecting a simple and easy connection to two separate producing formations through the same well bore.

The present invention lends itself very readily to removal, as well as re-installation of the upper packer 8,, since this is accomplished by first withdrawing tubing string Sill] and thereby releasing the setting pressure on packer S and allowing its anchoring elements to be retracted (FIG. 10), whereupon, by an upward pull applied to tubing string 50a, this string may be Withdrawn from lower packer S, in the manner previously described, and the string, together with upper packer S may then be pulled out of the well bore for whatever purpose such removal may be necessary. In order to re-complete the well in both formations, tubing string 59a carrying packer S may be re-inserted in the well bore and mandrel 38 re-introduced into the bore of lower packer S and lGCl-Lid therein, in the manner previously described. Thereupon tubing string 5% will be re-inserted in its setting sleeve D and its weight exerted to again set packer S to thereby complete the re-installation of the packers and re-completing the well to both formations.

The details of packer S do not form a part of the present invention and is disclosed primarily as an example of a weight-set type of packer which may be employed in conjunction with a hydraulic set packer in accordance with the present invention, having the straight-pull release features, above described, in order to effect multiple completions in wells. By having the straight-pull structure in the packer in accordance with the present invention, thereby avoiding the need for rotational manipulations of the tubing strings, the packer combination of a weight-set and a hydraulic-set packer, above described and illustrated in FIGS. 9 and 10, becomes completely practical and relatively simple in their installation and in effecting removal of both strings of tubing and the upper packers.

From the foregoing, it will be seen that the present invention provides a hydraulic set packer employing latching mechanism between the packer and the operating mandrel, by which the mandrel may be withdrawn or re-inserted into the packer merely by the straight-pull, as distinguished from rotational operations required with more conventional constructions. Moreover, by the construction described, the present type of packer may be employed with additional packers in multiple string completions, as described above, primarily by reason of the straight-pull release and connection features of the present invention.

Additionally, the present invention includes latching arrangements which assure against pre-mature setting of the packer while it is being run.

It will be understood that various alterations and modifications may be made within the illustrative details of the embodiment within the scope of the appended claims, without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

l. A well packer, comprising, a tubular body insertable in a well bore, a pair of longitudinally spaced anchor-andseal assemblies mounted about the exterior of the body, said assemblies including radially expandible anchor and seal elements and cooperating expander elements longitudinally movable along the body by axial forces oppositely directed thereagainst from between the assemblies to ex pand said anchor and seal elements to thereby anchor and seal said body to the well wall, fluid pressure-operated means comprising telescopically interconnected pision and cylinder elements slidably positioned on the body between said assemblies and operable by fluid pressure to move apart whereby to exert said oppositely directed axial forces on the respective expander elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight-pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means including cooperating latch elements on the mandrel and the body relatively positioned to be maintained in engagement when said piston and cylinder elements are relatively contracted and being releasable by said movement apart of said piston and cylinder element, to free the mandrel for said upward movement, means including said mandrel for supplying pressure fluid between said piston and cylinder elements, and means initially securing said anchor and seal elements to the body in retracted position and releasable in response to the axial force exerted on said assemblies by said fluid pressure-operated means.

2. A well packer, comprising, a tubular body insertable in a well bore, a pair of longitudinally spaced anchor-and-seal assemblies mounted about the exterior of the body, said assemblies including radially expandible anchor and seal elements and cooperating expander elements longitudinally movable along the body by axial forces oppositely directed thereagainst from between the assemblies to expand said anchor and seal elements to thereby anchor and seal said body to the well wall, fluid pressure-operated means comprising telescopically interconnected piston and cylinder elements slidably positioned on the body between said assemblies and operable by fluid pressure to move apart whereby to exert said oppositely directed axial forces on the respective expander elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straightpull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means being releasable by actuation of said fluid pressure-actuated means to free the mandrel for said upward movement, means including said mandrel for supplying pressure fluid between said piston and cylinder elements, and means initially securing said anchor and seal elements to the body in retracted position and releasable in response to the axial force exerted on said assemblies by said fluid pressure-operated means, said lower latch means comprising an external upwardly facing shoulder on said mandrel, and a plurality of angularly spaced radially movable ball elements mounted in the wall of said body, said ball elements being radially 9 projectible into latching engagement with said shoulder by engagement of the ball elements with said piston element when the latter is in its fully telescoped position in the cylinder element and being releasable from said' shoulder when the piston and cylinder elements are moved apart by said fluid pressure.

3. A multiple zone completion system for wells, comprising, a first pipe string insertable in a Well bore, a first packer mounted thereon and settable by hydraulic pressure supplied through said first pipe string to seal between the latter and the well bore wall, and a second packer mounted on the first pipe string above said first packer, a second pipe string, said second packer having a second bore therethrough adapted to receive said second pipe string in parallel relation to said first pipe string said second packer being settable by application of the weight of said second pipe string thereto to seal between both said pipe strings and the well bore wall, said first packer comprising a tubular body, a pair of longitudinally spaced anchor and seal assemblies mounted about the exterior of the body and radially expandible by fluid pressure into anchoring and sealing engagement with the well bore wall, a tubular operating mandrel forming a part of said first pipe string extending into the bore of said body, latch means securing said mandrel to said body and releasable by straight upward pull applied to the first pipe string to permit withdrawal of the mandrel from said first packer, and means including said mandrel for applying said hydraulic pressure to said assemblies to expand the same.

4. A multiple zone completion system for wells, comprising, a first pipe string insertable in a well bore, a first packer mounted thereon and including a body having a bore to receive said first pipe string, said first packer including hydraulic pressure actuated anchor means and seal means and being settable by hydraulic pressure supplied through said first pipe string to seal between the latter and the well bore wall, and a second packer having a second bore extending longitudinally therethrough mounted on the first pipe string above said first packer, a second pipe string said second packer being adapted to receive said second pipe string in said second bore in parallel relation to said first pipe string said second packer being settable by application of the weight of said second pipe string thereto to seal between both said pipe strings and the well bore wall, a tubular operating mandrel forming a part of said first pipe string extending through said bore of said first packer body, latch means securing said mandrel to said first packer body and releasable by straight upward pull applied to the first pipe string to permit withdrawal of the mandrel from the first packer and means including said mandrel for applying hydraulic pressure to said first packer to set the same.

5. In a well packer including a tubular body insertable in a well bore, a pair of longitudinally spaced anchor and seal assemblies mounted about the exterior of the body, said assemblies including radially expandible anchor and seal elements and cooperable expander elements longitudinally movable along the body by axial forces oppositely directed between the assemblies to expand said anchor and seal elements to thereby anchor and seal said body to the well wall, fluid pressure-actuated means slidably positioned about the body between said assemblies operable to exert said oppositely directed axial forces on the respective expander elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means including a latching shoulder on the mandrel and cooperating latch elements movably mounted on the body to project radially therefrom into latching engagement with said shoulder and held in said engagement by said fluid pres- 10 sure-actuated means and being releasable upon said actuation of said fluid pressure-actuated means to free the mandrel for said upward movement, and means including said mandrel for supplying pressure fluid to said fluid pressureactuated means.

6. A well packer, comprising, a tubular body insentable in a well bore, a pair of longitudinally spaced anchor and seal assemblies mounted about the exterior of the body, said assemblies including radially expandible anchor and seal elements and cooperating expander elements movable longitudinally along the body by axial forces oppositely directed thereagainst from between the assemblies to expand said anchor and seal elements to thereby anchor and seal said body to the well Wall, fluid pressure-operated means comprising telescopically interconnected annular piston and cylinder elements slidably surrounding the body between said assemblies and operable by fluid pressure to exert said oppositely directed axial forces on the respective expander elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight-pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means including a latching shoulder on the mandrel and cooperating latch elements movably mounted on the body to project radially therefrom into latching engagement with said shoulder and held in said engagement by said fluid pressure actuated means and being releasable upon said actuation of said fluid pressure-actuated means to free the mandrel for said upward movement, means including ports through the wall of the body and said mandrel for supplying pressure fluid from the interior of the mandrel between said piston and cylinder elements, and means initially securing said anchor and seal elements to the body in retracted position and releasable in response to the axial force exerted on said assemblies by said fluid pressure-operated means.

7. A well packer, comprising, a tubular body insertable in a well bore, a pair of longitudinally spaced anchor and seal assemblies mounted about the exterior of the body, said assemblies including radially expandible anchor and seal elements and cooperable expander elements longitudinally movable along the body by axial forces oppositely directed thereagainst from between the assemblies to expand said anchor and seal elements to thereby anchor and seal said body to the well wall, fluid pressure-operated means movably positioned on the body between said assemblies to exert said oppositely directed axial forces on the respective anchor elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight-pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means including a latching shoulder on the mandrel and cooperating latch elements movably mounted on the body to project radially therefrom into latching engagement with said shoulder and held in said engagement by said fluid pressure actuated means and being releasable upon said actuation of said fluid pressure-actuated means to free the mandrel for said upward movement, means including said mandrel for supplying pressure fluid to said fluid pressure-operated means, and means initially securing said anchor and seal elements to the body in retracted position and releasable in response to the axial force exerted on said assemblies by said fluid pressure-operated means.

8. A well packer, comprising, a tubular body insertable in a well bore, longitudinally spaced external abutment means mounted on the body, a pair of longitudinally spaced generally annular :anchor and seal assemblies mounted about the exterior of the body in abutting relation to said abutment means, each of said assemblies in- 11 eluding a conical tapered slip expander, an annular resilient seal element positioned between said abutment means and said expander, and a set of slips oircumferentially surrounding the tapered portion of the slip expander, said slips and said seal elements being radially expandible in response to axial movement of the slips toward the expanders to anchor and seal said body at longitudinally spaced points to the well wall, annular telescopically interconnected piston and cylinder elements slidably disposed about the body between said assemblies, the piston and cylinder elements being engaged with the slips of the respectively adjacent assemblies whereby to oppositely urge the slips toward their respective expanders when moved apart in response to fluid pressure introduced between the piston and cylinder elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight-pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means including a latching shoulder on the mandrel and latch elements movably mounted on the body to project radially therefrom into latching engagement with said latching shoulder when the piston and cylinder elements are relatively contracted and being releasable upon movement apart of said piston and cylinder elements to free the mandrel for said upward movement, means including said mandrel for directing pressure fluid through the interior of the body between the piston and cylinder elements, and means initially securing said slips to the respective expanders and to said body in relatively retracted positions, said last-mentioned means being releasable in response to the force of the fluid pressure exerted between the piston and cylinder elements.

9. A well packer, comprising, a tubular body insertable in a well bore, longitudinally spaced external abutment means mounted on the body, a pair of longitudinally spaced generally annular anchor and seal assemblies mounted about the exterior of the body in abutting relation to said abutment means, each of said assemblies including a conically tapered slip expander, an annular resilient seal element positioned between said abutment means and said expander, and a set of slips circumferentially surrounding the tapered portion of the slip expander, said slips and said seal elements being radially expandible in response to axial movement of the slips toward the expanders to anchor and seal said body at longitudinally spaced points to the well wall, annular telescopically interconnected piston and cylinder elements slidably disposed about the body between said assemblies, the piston and cylinder elements being engaged with the slips of the respectively adjacent assemblies whereby to oppositely urged the slips toward their respective expanders when moved apart in response to fluid pressure introduced between the piston and cylinder elements, a tubular operating mandrel extending into the bore of said body, longitudinally spaced upper and lower latch means releasably connecting the mandrel to the body, the upper latch means being of the straight-pull type constructed and arranged to be releasable by upward movement of the mandrel relative to the body, said lower latch means being releasable upon said movement apart of said piston and cylinder elements to free the mandrel for said upward movement, means including said mandrel for directing pressure fluid through the interior of the body between the piston and cylinder elements, and means initially securing said slips to the respective expanders and to said body in relatively retracted positions, said last-mentioned means being releasable in response to the force of the fluid pressure exerted between the piston and cylinder elements, said lower latch means comprising an external upwardly facing shoulder on said mandrel, and a plurality of angularly spaced radially movable ball elements mounted in the wall of said body, said ball elements being radially projectible into latching engagement with said shoulder by engagement of the ball elements with said piston element when the latter is in its fully telescoped position in the cylinder element and being releasable from said shoulder when the piston and cylinder elements are moved apart by said fluid pressure.

References Cited in the file of this patent UNITED STATES PATENTS 381,013 Hoadley Apr. 10, 1888 0,802,525 Newlin Apr. 28, 1931 2,121,002 Baker June 21, 1938 2,159,640 Strom May 23, 1939 2,270,900 Church Jan. 20, 1942 2,578,444 Ragan Dec. 18, 1951 2,715,444 Fewel Aug. 16, 1955 2,822,048 Tausch Feb. 4, 1958 2,902,093 Brown Sept. 1, 1959 2,903,066 Brown Sept. 8, 1959 2,950,761 Brown et al Aug. 30, 1960 

